There are 16 stored owner reports matching the engine leading-label group for the 2021 Mazda Mazda3 in our NHTSA-sourced dataset. These are unverified consumer reports and may not reflect confirmed defects.
This group counts stored reports whose component label starts with one of this site's matching prefixes, ignoring case. Each matching report counts once within the group. Components mentioned later in the label or only in the narrative are not searched. How component counts work
Loaded 16 of 16 matching reports.
Open the full vehicle complaint log (all categories)Spontaneous loss of power while driving on highway. Check engine light came on. Speed limited by car. Continues to vibrate especially at idle from cold start. Code P0304 intermittently popping up.
The thermostat malfunctioned on this vehicle, resulting in the thermostat remaining open and providing excess coolant to the engine, which in turn damaged internal components of the engine (compromises safety), decreased fuel economy, increased emissions (compromised safety), and decreased the life of the engine within the vehicle. It is available for inspection upon request. The vehicle has been inspected by an independent mechanic and will be inspected by the Mazda dealership in 7 days. There were no prior warnings until the engine malfunction notice appeared, the vehicle began to make jolts and stuttering sounds, and the temperature gauge within the vehicle failed to rise to optimal range. As this occurred while the vehicle was in use (safety concern), though I was pushing the gas there would be delayed response due to improper temperature, which increased the risk for an accident to occur.
The contact owns a 2021 Mazda Mazda3. The contact received notification of an unknown Class Action Lawsuit Number however, the part to do the repair was unavailable. The contact stated that the manufacturer exceeded a reasonable amount of time for the repair. The manufacturer was made aware of the issue. The contact had not experienced a failure. Parts distribution disconnect.
Low oil light - car is burning oil and only has 11,400 miles. Approx 3/4 to 1 quart missing...
Received Low Oil Level warning ... checked engine oil and it is under the minimum level on the dip stick. Car has only 11,725 miles
Turbo using/burning oil- Consumption issue.
Oil light has come one twice within 17,000 miles of owner ship. The first time at 4,800 miles and the second at 17,529 miles, the most recent was only 3,500 miles since the last oil change.
The engine is burning oil. Oil and filter were changed at 5000 miles. At about 9000 miles, the engine oil level light came on. Topped off with oil and took to dealer, they confirmed no oil leaks and changed the oil.
Excess oil consumption in engine. Low light came on around 5,000 miles and dipstick showed engine oil was at the minimum mark.
Engine is consuming excessive oil. Dealership states there is a TSB out but the fix is to keep topping the oil off. I would like an investigation to determine the root cause of the oil consumption on a new engine.
Driving on a remote highway in northern WI and low oil light illuminated, 1000 miles before oil change was due with less than 10k miles on the vehicle. Made it to a gas station and oil was a quart low. Vehicle burns over a quart every oil change interval, since this has been occurring since day 1 it is likely going to cause premature engine failure which would be a safety issue.
My Mazda 3 2.5T has been burning oil in excess. The car has a total of 24,000 miles and has been serviced 3 times. I have had to add oil in between every service. The oil has been completely burned off by 4,000-5,000 miles. I have noticed that other people have been posting about the same issues online. When talking to the dealership they state that they have noticed this issue with the 2.5T’s but offer no fix and seem to overfill the engine oil to try and compensate.
Low engine oil warning between oil changes. Burned 3+ quarts between 5000 mile and 10,000 mile service.
At around 3600 Miles my Mazda which I had for only a couple of months displayed a low engine oil light which required a visit to the dealership.This was under normal driving conditions.
After roughly 2,000 miles of driving, the low oil light comes on. The engine is burning oil. Mazda has issued a TSB on it, but they have taken no action to fix the issue. Right now they just top off the oil.
Purchased car in January 2020 and within a month/few thousand miles the low engine oil light came on. Almost two years later car continues to burn excessive oil triggering low engine oil light. Dealer doesn’t acknowledge an issue, Mazda still doesn’t have a repair. Owners required to pay for excess servicing until a repair is issued. This is a widespread problem impacting the engine.
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
NHTSA source checks for this vehicle year
Checks are recorded separately for each dataset, not for the whole page. Dates use UTC. A missing check date does not mean no records exist.
Vehicle import recorded: Apr 28, 2026. This is the stored import date, not confirmation that every source was successfully refreshed.